code: def build_label(text):
      label = ui.TextBlock2D()
      label.message = text
      label.font_size = 18
      label.font_family = "Arial"
      label.justification = "left"
      label.bold = False
      label.italic = False
      label.shadow = False
      label.background_color = (0, 0, 0)
      label.color = (1, 1, 1)
  
      return label
  
file_path: dipy/doc/examples/viz_advanced.py
imports: import numpy
  from dipy.data.fetcher import fetch_bundles_2_subjects, read_bundles_2_subjects
  from dipy.tracking.streamline import Streamlines
  from dipy.viz import actor, window, ui
label_desc: Use image node_id 5 for calling a global function with example usage: build_label(text) and returns: label